Friday, July 20, 2007

Using Softgrid, applications are virtualized and packaged in (basically) on file, streamed to the user and launched locally on the client. On the client, these applications run in a 'bubble' so that it is isolated from other virtual applications. One of the nice consequences of virtualization is that some applications that would normally not be server-based computing (SBC) compliant can be made so. This is a consequence of the fact that on the client, a user cache exists.

Let me give the example of an INI file that is used by application X to store user-related data. Normally, on a terminal server, this INI file would be shared by all users and thus only one user would be able to use the application at one time. Using Softricity, this INI file is virtualized and is configured to be 'user configuration' (see also here). This way, changes to this file are stored in a cache specific to the user (in the user's profile). Every user has its own version of the INI file and no conflicts can arise.

Setting the INI file as 'user configuration' is automatically done by the sequencer during the sequencing process and it is because the sequencer has certain rules saying 'This type of file needs to be user-specific'. In my case, the files that need to be user-specific are not yet created at the time of sequencing (they are later created normal usage of it. No broblem you say?! When a file is created inside a virtual directory (a directory that does not exist locally on the client, but comes with the virtual environment) it is stored cache! Yes, but in machine cache, not user cache!

What I would need in this specific case is a possibility to define which types of files need to be cache machine-wide and which user-based, not on the sequencer (see this SeqTypes tool by VirtualApp) but on the client. Or in other words, I would like to have the SeqTypes tool available on the Softgrid client. Has anyone experience or more information on this?